`requests-mock` recently changed its way to match URLs, paths are now
quoted when registering mocked URLs.
As Web API graph endpoint send HTTP requests to the Graph service
with SWHIDs in URL paths (containing ':' characters), those must
also be quoted or recent `requests-mock` will not find the registered
mocked URLs.
Also ensure tests still pass with older `requests-mock` versions.
Of course, I have tested that the endpoint still works as expected without mocked responses.
See https://github.com/jamielennox/requests-mock/commit/f072845